> I don't think waterfall is actually used in other disciplines, perhaps we were just cargo culting back then?
I think this is half right. There was quite a bit of cargo-culting going on. But the fundamental error was to try to apply the project-management process for the construction of other kinds of artefacts to the design of software. I wrote about this very topic here:
You're correct that no other engineering discipline attempts to use waterfall-style project management of its design process. They don't really use it in the construction process either (in practice, design tends to continue alongside construction), though it probably has at least been attempted.
It was no surprise to see that the authors of this piece are in fact among the originators of the Rational Unified Process. They claim to have corrected their mistake; in fact they are still pushing the same wrongheaded ideas as they were in the 1980s.
"They don't really use it in the construction process either (in practice, design tends to continue alongside construction)..."
For something like a high-rise office tower, the design decisions you can change after construction is in progress are quite limited. For example, you can't add ten more floors to the building as an afterthought, since that would involve adding extra elevator shafts, emergency stairways, water and sewage lines, etc. that would cause significant disruption to the floors of the building that have already been built. Similarly, redesigning the layout of a floor to accommodate twice as many people would require similar changes to stay compliant with building and safety codes.
I suppose if you're constructing a single-family house, there's much more leeway to change the design during construction - but it would still be costly.
I think this is half right. There was quite a bit of cargo-culting going on. But the fundamental error was to try to apply the project-management process for the construction of other kinds of artefacts to the design of software. I wrote about this very topic here:
http://www.zerobanana.com/essays/reclaiming-software-enginee...
You're correct that no other engineering discipline attempts to use waterfall-style project management of its design process. They don't really use it in the construction process either (in practice, design tends to continue alongside construction), though it probably has at least been attempted.
It was no surprise to see that the authors of this piece are in fact among the originators of the Rational Unified Process. They claim to have corrected their mistake; in fact they are still pushing the same wrongheaded ideas as they were in the 1980s.